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Date: Sat, 16 Feb 2013 07:43:48 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Raymond Jennings <shentino@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] SIGKILL vs. SIGSEGV on late execve() failures
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On Fri, Feb 15, 2013 at 11:20:18PM -0800, Raymond Jennings wrote:

> An even bigger question might be why an execve is allowed to get into
> an unrecoverable state to begin with.  Assuming that one builds the
> new mm_struct and whatnot BEFORE discarding old state, why would
> execve be in a position for a fatal error in the first place?

When would you kill the rest of thread group?  Take a look at de_thread() -
we are not just replacing ->mm during execve().  Signal delivery logics,
etc.